Published on 2022-08-07
It is Thursday. You are fixing a bug in a project you usually do not work on.
Just before you commit your changes, you notice some temporary files your
editor left behind in the git status output. So you add them to the
.gitignore file and commit those changes. You send your changes into review and
eagerly wait for someone to say And thank you for taking care of that missing
gitignore entry.
But to your surprise, the feedback you receive looks something like this:
There are a few things I do not want to know. And what editor/IDE you use to edit files is one such thing. So please remove your editor-specific ignore entries from the project's .gitignore file and place them into your personal ignore file. Thank you!
And if your reaction is My personal ignore file?, you should read on.
Yep. And git's built-in help will tell you the location of those files in its synopsis:
$ git help ignore
...
SYNOPSIS
$XDG_CONFIG_HOME/git/ignore, $GIT_DIR/info/exclude, .gitignore
...
If you read the manual's description section you will also get some information about what to put into each of those files. The mathematician in me also likes to think about those files using the following Venn diagram:
<--------------- developer-specific --------------->
.------------------------+-------------------------+--------------.
| ~/.config/git/ignore | $GIT_DIR/info/exclude | .gitignore |
'------------------------+-------------------------+--------------'
<----------- project-specific ----------->
I tend to call the ~/.config/git/ignore filea personal ignore file, and .gitignore file(s) project ignores. I have no special name for $GIT_DIR/info/exclude file since you can safely ignore it the in the vast majority of cases. I have been using git for more than ten years now and I used that ignore file location once.
During day-to-day activities, it is quite easy to determine where a particular ignore entry should go. The rule of thumb I use is:
If ignored entry pops into existence while I follow the build/test/release instructions, it should live in the repository's .gitignore file. Otherwise, it should be part of my ~/.config/git/ignore file.
If you follow my rule, you will most likely set up your personal ignore file once (when you set up your computer) and only work with project ignore files from then on.
If you need some inspiration, I would suggest you visit the github/gitignore repository. You should use ignore samples in the root of that repository as a source of inspiration for your project-specific ignore entries. For personal ignore entries, use files in the Global directory.
If you can keep your code sane, you should be able to track your ignores in two
locations ;) But if you ever get too confused by your setup, git has your back.
The git check-ignore -v command will tell you the source of the ignore
entry:
$ git check-ignore -v output/index.html content/articles/.*.swp .gitignore:1:output output/index.html ~/.config/git/ignore:4:[._]*.sw[a-p] content/articles/.art.rst.swp
Cheers!